During surgical procedures it is necessary to approximate tissue organ with surgical staples. Surgeons often use linear cutter stapling devices to suture body organs and tissues such as lung, esophagus, stomach, duodenum and other body organs. Such devices apply a plurality of laterally spaced rows of staples on opposite sides of a tissue cut.
Examples of such surgical staplers are disclosed in U.S. Pat. Nos. 4,633,861 and 4,892,244, the disclosures of which are incorporated herein by reference. The surgical stapler includes a pair of cooperating elongated jaw members. One of the jaws members includes a staple cartridge with at least two laterally spaced rows of staples and the other jaw member includes an anvil with staple closing depressions in alignment with the rows of staples in the cartridge. A pusher block is directed longitudinally along the jaws to sequentially eject staples from the cartridges in a manner that closes the staples against the anvil to form laterally spaced lines of staples through tissues that is gripped between the jaws. A knife is associated with the pusher block so as to move forward along the jaws to cut the tissue along the line between the previously formed staple rows.
When operating on tissue it is desirable to close open blood vessels (hemostasis) along the cut line. And in procedures that involve approximating lung tissue it is necessary to seal the lung to avoid air leakage (pneumostasis). U.S. Pat. No. 5,263,629 discloses a method and apparatus for achieving hemostsis along a staple line by utilizing a pledget material positioned adjacent to at least one surface of the tissue. The line of staples is formed so as to extend through the tissue and the absorbable pledget material. The pledget material is selected so as to substantially uniformly distribute pressure along the staple line and thereby cause substantial hemostasis along the tissue cut. Preferred materials for these pledgets are sterile absorbable tightly woven fabrics. The pledgets may be secured to the stapler by spaced apart ultrasonic welds or spaced apart adhesive bonds.
The present invention provides an improved surgical stapling apparatus wherein the pledget material or buttress is an soft, compliant, bioabsorbable, foam material that is easy to cut and provides better sealing for hemostasis and pneumostasis which maybe releasably attached to the stapler by a low melting or liquid bioabsorbable polymer.